Medically reviewed by Stella Bard, MD A rheumatoid factor (RF) test detects rheumatoid factor, a type of antibody (proteins that fight off harmful substances) in your blood. RF antibodies sometimes ...

A little less than a third of people who have psoriasis will get psoriatic arthritis. Doctors can't yet tell who before it happens, though. Usually, you'll have the skin symptoms first.

That’s because the twisting motion required to throw a slider can damage delicate ligaments in the elbow. If you have any of these symptoms, your doctor may be able to diagnose cubital tunnel ...